During operation of a nuclear power plant, different materials are deposited upon heating surfaces of the nuclear primary system, thereby causing a change in the heating surface. In most instances, material collects upon the heating surface, thereby causing an insulating effect between the heating surfaces and the coolant of the primary system. In some instances, the material deposited upon the heating surface can cause localized corrosion and/or pitting of the surface.
Operators of nuclear power systems strive to minimize the amount of deposits upon heating surfaces, thereby allowing the best possible performance from reactor systems under controlled conditions. Over time, the deposition of materials upon the heating surfaces can affect the overall economic operability of the nuclear power reactor. In order to increase the economic viability of the nuclear power station, it is desired to ascertain the exact nature of the materials deposited upon the heating surfaces as well as to determine the source of these deposits.
Currently, there is no systematic, well-defined approach to the study of deposits such as nuclear steam generator deposits, or other radioactive crystalline structures in their “as found” condition in irregularities at the surface of the equipment. There is no known way to combine various electron microscopy methods in analytical electron microscopy and/or sample preparation to achieve maximum information about materials such as Chalk River Unidentified Deposits (CRUD), nuclear steam generator deposits or other radioactive deposits to determine these deposits constituents in their “as found” condition for unadulterated portions of the deposits located in irregularities at the surface of the equipment on which they are found.
There is therefore a need to develop a comprehensive method to study deposits, such as nuclear steam generator deposits and CRUD, to determine the deposits crystalline structure.
There is a further need for a method which allows the study of these deposits in an economical and safe manner.